MACD

Gerald Appel's MACD (Moving Average Convergence/Divergence) indicator shows the relationship between two moving averages
of prices. MACD is derived by dividing one moving average by another. It is based on the point spread difference between
two exponential moving averages (EMA) of the closing price.

The basic MACD trading rule is to sell when the MACD falls below its signal line and to buy when the MACD rises above its signal line.

Some analysts use MACD as an oscillator and believe it is most effective in wide-swinging trading markets. They
believe that when the MACD rises dramatically, it is likely that the security's price is overextending and will
soon return to more realistic levels.

Other analysts prefer to use MACD as a trend-following indicator, attempting to spot divergences in chart patterns.
For example, a bearish divergence occurs when the MACD is making new lows while prices fail to reach new lows. A
bullish divergence occurs when the MACD is making new highs while prices fail to reach new highs. These divergences
are most significant when they occur at relatively overbought/oversold levels.

The MACD indicator in BigCharts references the following default parameters: